DESCRIPTION: (Adapted from Applicant s Abstract) Dendritic cells (DCs) are recognized as the key controllers of the immune system, including immune aspects of clinical medicine. DC biology continues to develop in significant and surprising ways. There are new subsets of DCs with different functions; new maturation stimuli that control the initiation of immunity; new markers to visualize DCs in lymphoid tissues and pathologic states; new molecular mechanisms that control DC migration and lifespan; and new therapies aimed at manipulating DC physiology. Therefore, it is straightforward to devote an entire meeting to DCs themselves. However, it is additionally important to emphasize the developments in DC biology that interface with other active areas of immunobiology and medicine. The main interfaces of this multidisciplinary meeting comprise 1) the cell biology of antigen presentation, including the regulated function of intracellular MHC II compartments, the exogenous pathway for presentation on MHC class I, and nonclassical presenting molecules like CD1; 2) T cell costimulation, including the clustering of MHC and accessory molecules to form the immunological synapse; 3) the role of DCs in the regulation of T cell function, including Thl/Th2 subsets, regulatory T cells, and peripheral tolerance; 4) the interaction of infectious agents with DCs, including emerging viral vectors for expression of recombinant genes; and 5) human immunotherapy, using DCs as adjuvants. The meeting will highlight the participation of younger scientists through the inclusion of longer talks by rising new investigators, shorter presentations selected from the abstracts, and several workshops in critical areas. The program and the breadth of participation will make this meeting a must for the many students and postdocs who are now providing the advances in this field.